A 915-MHz binary frequency-shift keying (BFSK) transmitter is proposed in this letter. The proposed transmitter architecture allows relaxing the frequency-tuning requirement of the conventional Internet of Things transceiver by the frequency-tripling signal-path topology. The tuning-range requirement is significantly improved down to 4% with the proposed signaling scheme, and this results in the ultralow-power synthesizer implementation. The proposed frequency tripler provides good spur rejection performance, and the adoption of a class-D switching power amplifier (PA) further improves the efficiency of the BFSK transmitter. Implemented in a 55-nm CMOS technology, the proposed transmitter achieves the output power of 5.5 dBm and 31.9% efficiency with only $207~\mu \text{W}$ of power consumption from the synthesizer.

中文翻译：

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采用三倍频器和 207-$\mu$ W 合成器的 5.5-dBm、31.9% 效率 915-MHz 发射器

这封信中提出了 915 MHz 二进制频移键控 (BFSK) 发射机。所提出的发射器架构允许通过三倍频信号路径拓扑放宽传统物联网收发器的频率调谐要求。使用建议的信令方案，调谐范围要求显着改善至 4%，这导致了超低功耗合成器的实现。建议的频率三倍器提供了良好的杂散抑制性能，并且 D 类开关功率放大器 (PA) 的采用进一步提高了 BFSK 发射机的效率。采用 55 纳米 CMOS 技术实现的发射器实现了 5.5 dBm 的输出功率和 31.9% 的效率，而合成器的功耗仅为 $207~\mu\text{W}$。